I guess the simplest answer is that coming from a Christian pov, I don't believe that the Qu'ran is the word of God because it doesn't give glory to Jesus who is God. To minimize His status to being that of a man renders the Qu'ran instantly devoid of spiritual merit.
From my personal pov based on quotes from the Qu'ran and some of the Hadith, as well as listening to Islamic preaching on tv....(and let me be honest by saying that I have not read the Qu'ran cover to cover- I hate it when non Christians try to tell me how they know my bible better than me so I won't patronize you in that way), Mohammed made up this religion for one of either two reasons:
a: He was deluded by spiritual deception and honestly believed what he was preaching.
b: He knowingly made it up as a bid for personal power.
Personally, the latter seems to be the case for me. I truly do not mean this to be offensive Adeeb, and am only saying this because it relates to your question... but Islam fairly reeks of being man made in my opinion. Christianity is all about RELATIONSHIP. It's what God desired from the very first moment in the garden. Man ruined this perfect accord, and so sin came into the world, and into the hearts of humanity. But, you can see all through the bible how God is constantly wooing His bride back to Him, to mend that same relationship. There are no specific *things* or tasks we have to complete or fill out on a daily basis in order to gain God's favour, we're simply to love Him with all our hearts, souls and very beings!!! Being in accord with Him, helps us to mature in Christ and to become like Him, think like Him... in other words it is the ONLY way we can hope to shed our sinful nature. That relationship that I'm referring to- is the ONLY way we can truly be what the world considers as *good*. For example, if we are walking in perfect love with our Creator, and TRULY living out His commandment to love each other more than ourselves, we will always be looking for ways to help our fellow man, change and affect lives in a positive way. In other words, no one will need to tell us to feed the poor- we'd be doing it out of a sincerity that can't be there if it's a
rule we must follow. Which brings me to my next point.
If Christianity is all about relationship, then Islam is all about religion. You have five pillars of your faith.
*making a pilgrimage to Mecca if you are able to at least once in your life.
*Alms giving to the poor and needy
*Praying five times a day facing Mecca
*Observing Ramadan
*Declaration of faith that there is only one God.
Now, let's look at each one, and critically determine how it would better your walk with God.
- Pilgrimage/ hajj: As a Christian, God's commandments are no longer on a piece of stone. He is not to be found in any man made temple or building. He is inside of ME! I grow in grace daily because I have Him nurturing me, guiding me and helping me. I honestly can't see how making a trip to a birthplace of any of the prophets would be an integral part of serving God or living as He would have me life. So my question is from your own personal pov, how has hajj improved your walk with God? Has it helped you live a sinless life, or a life abounding in love?
-Alms giving: Again, I must refer to my previous point about growing in a personal relationship with Christ. I find personally, that the more I experience Him, the more I want to be a light for His people. On my own I am nothing special, a true sinner. I will admit that I can be selfish which I know makes God so sad. BUT (and here is the great part), He is changing me daily! Sometimes I can't believe how gracious He is to soften this imperfect heart of mine to the point where I freely and willingly and openly *want* to give to people. Not just money, but also time and other resources. Now I give not because I *have* to, but because I want to. God values a cheerful giver. After all, if you receive something from someone who was forced into giving a gift to you, and another gift from a person who just really wanted to give it to you... which one would mean more? Which one would feel more "real" more sincerely from the heart? So my question to you is this: How does having the rule to give alms better the condition of your heart? Will you concede that men/women can (and do) do things in this world for the wrong reasons, and not necessarily from the goodness of their heart? Do you believe that the motivation behind a gift is a factor in determining the worth of the gift?
-Prayer 5x: As a Christian, I consider prayer to be one of the greatest privileges that God has granted me. Imagine...me- ME able to commune with the Creator of Heaven and earth!!! Imagine that He actually wants to hear from me? Wow. I can't tell you how that makes me feel

When I pray it's a conversation. I thank God for His goodness, for His provision, for his mercies. I petition Him on behalf of myself and loved ones, I confess my sins and struggles and beg Him for help and strengh and guidance. I do this all day. Sometimes when I'm working, washing my dishes or mopping the floor. When I wake up, when I go to sleep. My day is one long conversation to God. I don't need to be told to pray a certain number of times to Him...I pray because I literally NEED to do it. My heart will cry out to Him even if my mouth doesn't! My spirit is in desperate need to be heard by Him. So my question is much the same as the last one... say you have someone in your life who is very special to you. Your heart is filled to bursting with love for them and you always want to talk to them. Would you rather the sweet spontanaity of continuous verbal intimacy, or would you prefer them stick to a rule book and talk to you for (x) amount of minutes (x) amount of times per day??
-Ramadan: As a Christian, I believe that fasting is an integral part of our spiritual growth. I fast when I have that tugging in my spirit letting me know "it's time". Perhaps it's about a situation, perhaps it's just time for a spiritual cleanse and repentance session. Whatever it may be I do it for God because I *want* to. I make the sacrifice willingly without being told to. In return, God blesses me with a clarity that I wouldn't have attained otherwise. His voice is more audible and I can draw closer to Him through this sacrifice. I come back yet again to the same brick wall as I have with my last few points regarding ramadan. How does it please God that you fast because you *have* to? And a personal question to you (no sarcasm intended)- would you mind sharing with me the benefits you've received through fasting?
-Declaration that there is only one God: I don't have any issues with this. In fact, this is the only one I can actually embrace. I too believe there is only one God, and am happy to tell anyone who'll listen to me
So I guess my conclusion, is that apart from the last point, it's pretty clear that Islam is not about a relationship with God. It's a paint by numbers attempt to not tick God off. To present you with an analogy I've used with fellow Christians who are too legalistic, I think there is a huge difference in trying to please someone and just trying not to have them angry at you. The Christian walk is designed by God, for man to please God. It's designed for His children to be in a relationship with Him and for both parties to bask in each other's love. Islam on the other hand (and from my admittedly biased Christian pov) was designed by man, ostensibly for man to try to
not tick God off. There is no love, no grace, no fellowship with your Creator and I find that incredibly empty and sad.
If you've actually read all this (boy my fingers are getting tired

) then I sincerely thank you. Please know that I count many Muslims to be great friends of mine. I may not agree with your theology, but I hope I never come across as bigotted or resort to using crass media sensationalized theories to strengthen my point. I've tried to be as analytical as possible without using terminology that could wound another of a different culture or religion so I really do hope you take this in the spirit it's intended!!